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In esophageal squamous cell carcinoma, the number of dissected lymph nodes (LNs), including those along the recurrent laryngeal nerves (RLNs), influences prognosis and nodal staging accuracy. However, dissection of LNs along the RLN increases the risk of complications, especially RLN palsy. Therefore, complete dissection of these LNs with prevention of RLN palsy is recommended. We present herein a new method for lymphadenectomy along the right RLN, named the Pincers maneuver, during thoracoscopic esophagectomy in the prone position (TEP). The fundamental concept in this new method is to first exfoliate the two-dimensional membrane (lateral pedicle), which includes the right RLN, LNs along the right RLN, and the primary esophageal artery, from the right side of the trachea toward the neck. Using a Pincers strategy, closing in from the inner and outer sides of the two-dimensional membrane (lateral pedicle), lymphadenectomy along the right RLN toward the right inferior thyroid artery should be easy. This technique was evaluated in 30 consecutive cases of TEP for squamous cell cancer. There were 15 patients who underwent the new method (Pincers maneuver; Pm) and 15 patients who underwent the conventional method (Cm). There were no significant differences between the two groups in the duration of the thoracic procedure and dissection along the right RLN. No intraoperative and postoperative morbidity related to the right RLN was observed in either group. The Pm group had a higher number of dissected LNs along the right RLN than the Cm group (6.3 vs 3.1, p = 0.044). The Pincers maneuver for lymphadenectomy along the right RLN during TEP is technically safe and feasible. It increases the number of dissected LNs along the right RLN.

Minimally invasive esophagectomy (MIE) has less morbidity than the open approach. In particular, thoracoscopic esophagectomy in the prone position (TEP) has been performed worldwide. Using the cumulative sum control chart (CUSUM) method, this study aimed to confirm whether a trainee surgeon who learned established standards would become skilled in TEP with a shorter learning curve than that of the mentoring surgeon. Surgeon A performed TEP in 100 patients; the first 22 patients comprised period 1. His learning curve, defined based on the operation time (OT) of the thoracic procedure, was evaluated using the CUSUM method, and short-term outcomes were assessed. Another 22 patients underwent TEP performed by surgeon B, with outcomes compared to those of surgeon A’s period 1. Using the CUSUM chart, the peak point of the thoracic procedure OT occurred at the 44th case in surgeon A’s experience of 100 cases. With surgeon A’s first 22 cases (period 1), the peak point of the thoracic procedure OT could not be confirmed and graph is expanding soaring at CUSUM chart. The CUSUM chart of surgeon B’s experience of 22 cases clearly indicated that the peak point of the thoracic procedure OT occurred at the 17th case. The rate of recurrent laryngeal nerve palsy for surgeon B (9 %) was significantly lower than for surgeon A in period 1 (36 %) (p = 0.0266). There is some possibility for a trainee surgeon to attain the required basic skills to perform TEP in a relatively short period of time using a standardized procedure developed by a mentoring surgeon. The CUSUM method should be useful in evaluating trainee competence during an initial series of procedures, by assessing the learning curve defined by OT.

Thoracoscopic esophagectomy with the patient in the prone position (TEP) is now being performed as minimally invasive esophagectomy for esophageal cancer. This study examines the short-term outcomes and the learning curve associated with TEP. One surgeon (“Surgeon A”) performed TEP on 100 consecutive patients assigned to three periods based on treatment order. Each group consisted of 33 or 34 patients. The outcomes of the three groups were compared to define the influence of surgeon expertise. Outcomes improved as Surgeon A gained experience in performing this operation, as evidenced by reduced thoracic operative times between periods 1 and 2, and then between periods 2 and 3 (p = 0.0033 and p = 0.0326, respectively); an increased number of retrieved chest nodes between periods 1 and 2 (p = 0.0070); and a decline in recurrent laryngeal nerve (RLN) palsy between periods 2 and 3 (p = 0.0450). Period 2 was the pivotal period for each learning curve. An individual surgeon’s learning curve over the course of 100 TEP procedures had three outcomes: a shortened operative time, a higher number of retrieved chest nodes, and a decreased rate of RLN palsy. Approximately 30–60 cases were needed to reach a plateau in the TEP procedure and a reduction in the morbidity rate.

This review describes a series of studies on the Na+ superionic conducting glass-ceramics with Na5YSi4O12 (N5)-type structure synthesized using the composition formula of Na3 + 3x − yR1 − xPySi3 − yO9 for a variety of rare earth elements, R, under the appropriate composition parameters. In the crystallization of N5-type glass-ceramics, its relatives (Na3YSi3O9 (N3)- and Na9YSi6O18 (N9)-type glass-ceramics) structurally belonging to the family of Na24 -3xYxSi12O36 were found to crystallize as the precursor phase at low temperatures. In order to produce N5 single phase glass-ceramics, the concentration of both phosphorus and rare earth was found important. The meaning of the composition was evaluated by kinetic study on the phase transformation of metastable N3 or N9 phases to stable N5 phase with Na+ superionic conductivity. The possible combinations of x and y became more limited for the crystallization of the superionic conducting phase as the ionic radius of R increased, while the Na+ conduction properties were more enhanced in the glass-ceramics of larger R. These results are discussed in view of the structure and the conduction mechanism. Also discussed were the microstructural effects on the conduction properties, which were dependent upon the heating conditions of crystallization. These effects were understood in relation to the grain boundary conduction properties as well as the transmission electron microstructural morphology of grain boundaries. Recent researches on structural control of the glass-ceramic Na+ superionic conductors are also introduced. The optimum conditions for crystallization were discussed with reference to the conduction properties and the preparation of crack free N5-type glass-ceramics. The effects of Si substitution with the various elements with tetrahedral oxygen coordination structure and Y substitution with the various R elements were also discussed on ionic conductivity of N5-type glass-ceramics, respectively. In addition, the results on control of the structure by bias crystallization of glasses in an electric field were presented.

In this paper, we examine the power generation performance of a rotational electret power generator theoretically and experimentally using electrostatic induction based on the properties of hydroxyapatite (HAp) ceramic electrets; the two surfaces of the electrets have opposing polarities. The HAp electrets have long-term stability in comparison with polymer electrets, which are more commonly used. The theoretical power output is proportional to the square of the total surface area of electrets per block of the stator, frequency of the rotor, and surface electric potential of the electret. Moreover, the power output is proportional to the square of the inverse of the air gap between the rotor and electrets. The behavior of power outputs obtained under different experimental conditions correlated with our theoretical prediction. The maximum output power generated by our prototype electret generator was 3.6 μW with the frequency of the rotor being 24 Hz.

The role of ceramic biomaterials in the repair of bone defects varies from materials that purely fill the physical defects of the injured bone to scaffolds that control cellular behaviors. In this study, we investigated the osteoclast formation related to the osteoconductivity of ceramic biomaterials. We performed in vitro cocultures using osteocyte-like cells and bone marrow cells and in vivo implantations of hydroxyapatite with different amounts of carbonate substitutions into rat femurs. The analyses of the cocultures revealed that bone marrow cells differentiated into osteoclasts and were activated to resorb the substratum when grown on hydroxyapatite with higher numbers of carbonate substitutions. This was indicated by the expression of macrophage colony-stimulating factor and receptor activator of the nuclear factor-kappa B ligand that induce osteoclast differentiation by osteocyte-like cells and characteristic resorption pits. The increased osteoclastogenesis in vivo was observed near the hydroxyapatite with more carbonate substitutions after implantation into the rat femurs. These results suggest that the content of carbonate ions in an apatite crystal lattice has an inductive effect on osteoclastogenesis in the vicinity of the implanted ceramic biomaterial. The results contribute to the design of biomaterials that would be resorbed by osteoclasts after fulfilling their primary function as scaffolds for cell growth and eventually bone regeneration.

Gastrointestinal stromal tumors (GISTs) are relatively common in neurofibromatosis type 1 (NF 1) patients. Approximately 90% of GISTs associated with NF 1 are located in the small intestine, while sporadic GISTs are most commonly located in the stomach. Here we report an extremely rare case of an NF 1 patient with multiple gastric GITs (90 or more) but without multiple small intestinal tumors. A 63-year-old female patient who had a history of NF 1 underwent surgery for a gastric neuroendocrine tumor and gastric submucosal tumor (SMT). During the operation, multiple small nodules were identified on the serosal surface of the upper stomach. SMT and multiple nodules on the serosal surface were diagnosed as GISTs consisting of spindle cells positive for KIT, CD34, and DOG-1. Both GIST and the normal gastric mucosa showed no mutations not only in the c-kitgene (exons 8, 9, 11, 13, and 17) but also in thePDGFRAgene (exons 12, 14, and 18). This patient is being followed up without the administration of a tyrosine kinase inhibitor.

Sodium-ion conductive glass-ceramics of Na5FeSi4O12 were successfully synthesized through the crystallization of glasses with the composition Na5FeSi4O12. The optimum crystallization conditions and the kinetics of the glasses were examined by differential thermal analysis. The characterization of crystallization and conduction properties were performed on thus obtained glass-ceramic Na5FeSi4O12 by a non-isothermal modified Kissinger and complex impedance methods, respectively. The activation energy for crystallization was 279 kJ mol−1 and the sodium-ion conductivity was obtained as 1.33 × 10−3 S cm−1 at 300 °C. To improve the conductivity with a small amount of Si-substitutes, Na5FeSi4O12-isostructural derivatives containing such as B, Al, and Ga were also prepared according to the same crystallization process of glasses with the composition Na5.1FeM0.1Si3.9O12 (M = B, Al, Ga). Without phase separation, the ionic conductivities of glass-ceramics were enhanced up to 1.69 × 10−3 at 300 °C on Na5.1FeB0.1Si3.9O12, whereas decreased down to 1.30 × 10−3 and 1.12 × 10−3 S cm−1 at 300 °C on Na5.1FeAl0.1Si3.9O12, and Na5.1FeGa0.1Si3.9O12, respectively.

Background: The enhancement of antitumor immune response with radiotherapy was reported recently, but there are few reports on the mechanism of the effect in rectal cancer. In neoadjuvant chemoradiotherapy (NACRT) for rectal cancer, we reported that CD8+T cells in tumor tissues were highly induced and the density of CD8+T cells were a favorable prognostic factor. The aim of the present study was to elucidate the dynamics of CD8+T cells in the tumor after irradiation. Methods: For this purpose, we established a therapeutic model of irradiation for BALB/c mice inoculated with CT26 colon cancer cell line. They are irradiated with a single dose of 10Gy after 14 days. We analyzed CD8+ T cells infiltration of both irradiated (mice) and no treated (control) mice by flow cytometry. Intratumor CD8+ T cells were fractionated into three populations according to the expression of PD-1 and Tim-3. The numbers and ratios were measured and their dynamics were analyzed. Next, purified CD8+T cells from the tumor with or without irradiation and intracellular cytokines such as IFNγ, TNF-α, and IL-2 were measured. Finally, we analyzed mice treated with FTY720 to test newly infiltrating T cell infiltration after irradiation delivered locally into tumors. Results: In our model, elevated numbers of tumor-infiltrating CD8+ T cells between day11 and day18 after irradiation were observed in tumors of mice compared to control. We observed that the number of PD-1+Tim-3+ CD8+ T cells, that comprised the major population among intratumoral CD8+ T cells, were markedly increasing in irradiated mice. Functionally, intratumoral CD8+ T cells in irradiated mice produced more INF-γ compared to control. Especially, PD-1+Tim-3+ CD8+ T cells enhanced INF-γ production. Among the three populations, PD-1+Tim-3+ CD8+ T cells contained the largest fraction of effector memory (CD44hiCD62Llow) cells, but the lowest fraction of central memory (CD44hiCD62Lhi) cells. Finally, after administration of FTY-720, the decrease rate of intratumoral CD8+ T cells in irradiated mice was much higher than in control. This results suggest that newly infiltrating CD8+ T cell number in irradiated mice was higher than in control. Conclusions: In mouse model of irradiation, there were newly infiltrating CD8+ T cells which was markedly increased compared to the control. This population may be involved in the increase of intratumor CD8+ T cells and may contribute to antitumor effects. This change is expected to trigger further therapeutic intervention. Citation Format: Kimihiro Yamashita, EIJI Fukuoka, Yutaka Sugita, Akira Arimoto, Akihiro Watanabe, Gousuke Takiguchi, Naoki Urakawa, Hiroshi Hasegawa, Masashi Yamamoto, Shingo Kanaji, Yoshiko Matsuda, Takeru Matsuda, Takeru Matsuda, Taro Oshikiri, Tetsu Nakamura, Satoshi Suzuki, Yoshihiro Kakeji. Radiotherapy enhances newly infiltrating CD8+T cells into tumor tissue to increase intratumor CD8+T cells and exert an anti-tumor effects [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2260.

Background: Invariant natural killer T (iNKT) cells have been shown as an ideal immunotherapeutic target of which the activation via α-galactosylceramide (α-Gal) conjugated with the MHC class I- like CD1d molecule induces both innate and adaptive immune system. With transfection of antigen information, α-Gal loaded CD1d expressing cells can act as a vector to enhance the antigen specific immune responses. Though transfection of antigen information coded as mRNA is popular, the process of extracting mRNA or identifying tumor peptide is sometimes too complicated. Electroporation (EP) has been reported as a way to induce substances easily into cells. We applied EP to deliver the antigen into the vector for iNKT cell activation just as a simple procedure. In this study, we aimed to show a feasibility of EP as a method to deliver the antigen into α-Gal loaded dendritic cells (DCs), a naturally CD1d expressing vector, in terms of inducing antigen specific antitumor responses. Methods: DCs were generated from bone marrow of C57BL/6 mice. Ovalbumin (OVA) was electroporated to DCs as a tumor model antigen. To load α-Gal, DCs were cultured with α-Gal for 48 hours. We compared the antitumor responses of α-Gal loaded DCs with or without electroporated OVA in C57BL/6 mice. In subcutaneous tumor model, mice were prophylactically administered each type of DCs intravenously followed by subcutaneous injection of EG7, which is OVA induced EL4, thymoma (n = 5, respectively). We evaluated the tumor size and the survival rate. We also evaluated the antitumor responses of which EP density of OVA can induce efficient antitumor response. Results: With electroporated OVA, tumors didn't grow in mice administered α-Gal loaded DCs whereas tumors in mice administered α-Gal loaded DCs without electroporated OVA aggressively progressed (P < 0.05). In mice administered α-Gal loaded DCs with electroporated OVA, no death was observed during the whole observation period. Survival rate was significantly better for mice administered α-Gal loaded DCs with electroporated OVA than those administered α-Gal loaded DCs without electroporated OVA (P < 0.05). The α-Gal loaded DCs also induce more memory progenitor cells than control group (P < 0.01). Conclusion: α-Gal loaded DCs with electroporated OVA showed significantly higher rate of tumor rejection and longer survival in the mice model inoculated OVA-induced tumor comparing to α-Gal loaded DCs without electroporated OVA. EP was feasible as a way to deliver the antigen into the vector which induced antigen specific antitumor responses. We are trying to show the activity of antigen-specific cytotoxic T lymphocytes following the administration of α-Gal loaded DCs with electroporated antigen. Citation Format: Akihiro Watanabe, Kimihiro Yamashita, Akira Arimoto, Yutaka Sugita, Eiji Fukuoka, Takashi Kamigaki, Rishu Takimoto, Yoshihiro Kakeji. Antigen specific antitumor effect induced by antigen-electroporated, natural killer T cell ligand-loaded dendritic cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6534.

Background We report a rare case of gastrointestinal stromal tumors (GISTs) in Carney’s triad, successfully treated using laparoscopic gastrectomy with lymph node dissection after chemotherapy. Case presentation A 21-year-old woman presented to our hospital for treatment of recurrent GISTs. The patient had been admitted for treatment 11 years prior, with black stools being the chief presenting complaint at that time. On examination at that time, multiple submucosal tumors in the pyloric antrum and multiple pulmonary tumors had been observed. She underwent open partial gastrectomy, and the diagnosis of GISTs was confirmed. She was administered tyrosine kinase inhibitors to treat lung metastases from 2 months after surgery. Due to the increasing size of the lung tumors, a right upper lobectomy was performed 9 years after the index gastric surgery. Histopathological examination of the lung specimen, in combination with re-examination of the gastric specimens, was indicative of incomplete-type Carney’s triad. Eleven years after the index gastric surgery, multiple GISTs were observed in her entire stomach. Tumor biopsy revealed a succinate dehydrogenase deficiency, confirming the diagnosis of recurrent GISTs. For treatment, the patient underwent laparoscopic completion gastrectomy, with D1 plus lymph node dissection. Conclusion This is a first case report of completion gastrectomy performed laparoscopically for the treatment of GISTs associated with incomplete-type Carney’s triad. The recurrent GISTs developed over a protracted period of 11 years from the index gastric surgery to tumor recurrence.

In esophageal squamous cell carcinoma (ESCC), lymph nodes (LNs) around the subcarina and main bronchi are thought to be highly involved. Therefore, complete dissection of these LNs with preservation of the pulmonary branches of the vagus nerves, which control important pulmonary functions, is recommended. The aim of this retrospective study was to investigate the feasibility of reliable method for lymphadenectomy around the subcarina and main bronchi, named the medial approach, during thoracoscopic esophagectomy in the prone position (TEP). This was a case-matched control study of patients who underwent TEP for ESCC. The fundamental concept in this method is to first exfoliate the LNs around the subcarina and main bronchi from the pericardium. Developing the operative field contributes to visualizing and preserving the pulmonary branches of the right vagus nerve. Twenty-three patients who underwent the medial approach and 23 patients who underwent the conventional approach were selected by the use of propensity score matching to compare the operative outcomes. The medial approach significantly reduced operative time for procedure (16 ± 3 vs 30 ± 6 min, p

AIM To evaluate the clinical significance of lateral pelvic lymph node (LLN) size in predicting pathological metastasis and prognosis in rectal cancer treated with preoperative chemoradiotherapy (CRT) followed by surgery. PATIENTS AND METHODS Fifty-two patients with rectal cancer who underwent curative surgery after preoperative CRT were included. Fifteen patients underwent total mesorectal excision (TME) alone, while 37 patients underwent TME with LLN dissection for clinical LLN metastasis. RESULTS Pathological metastasis was identified in seven (2.6%) out of 270 resected LLNs in six (16.2%) out of 37 patients. The cut-off value of the short-axis diameter was 7.0 mm before and 6.0 mm after CRT. The 5-year recurrence-free survival rate was significantly higher in patients with LLNs

miRNAs are key players in the integrated regulation of cellular processes and shape many of the functional properties that define the “cancer stem cell” (CSC) phenotype. Little is known, however, about miRNAs that regulate such properties in human colorectal carcinoma. In this study, we compared the expression levels of 754 miRNAs between paired samples of EpCAM+/CD44+ cancer cells (enriched in CSCs) and EpCAM+/CD44neg cancer cells (with CSC depletion) sorted in parallel from human primary colorectal carcinomas and identified miR-221 as the miRNA that displayed the highest level of preferential expression in EpCAM+/CD44+ cancer cells. High levels of miR-221 expression were associated with Lgr5+ cells in mouse colon crypts and reduced survival in patients with colorectal carcinoma. Constitutive overexpression of miR-221 enhanced organoid-forming capacity of both conventional colorectal carcinoma cell lines and patient-derived xenografts (PDX) in vitro. Importantly, constitutive downregulation of miR-221 suppressed organoid-forming capacity in vitro and substantially reduced the tumorigenic capacity of CSC populations from PDX lines in vivo. Finally, the most abundant splicing isoform of the human Quaking (QKI) gene, QKI-5, was identified as a functional target of miR-221; overexpression of miR-221–reduced QKI-5 protein levels in human colorectal carcinoma cells. As expected, overexpression of QKI-5 suppressed organoid-forming capacity in vitro and tumorigenic capacity of colorectal carcinoma PDX cells in vivo. Our study reveals a mechanistic link between miR-221 and QKI and highlights their key role in regulating CSC properties in human colorectal cancer. Significance: These findings uncover molecular mechanisms underlying the maintenance of cancer stem cell properties in colon cancer.

Transmesenteric hernia is a rare cause of small bowel strangulation in adults and, to our knowledge, no one has reported the existence of two mesenteric defects in an adult. Our patient was a 73-year-old Japanese woman who presented to our emergency department complaining of abdominal pain and nausea. Computed tomography with contrast enhancement revealed a closed loop obstruction in the pelvis, suggesting small bowel strangulation due to an internal hernia. The emergency exploratory laparotomy indicated a small bowel strangulation caused by a transmesenteric hernia. With the examination across whole parts of the mesentery, we identified another small defect. Both defects were closed by suture intraoperatively, and the patient’s postoperative course was satisfactory. Searching for whole parts of the mesentery after the reduction of a hernia can help prevent the recurrence of internal hernias.

Background and objective: In patients with acute appendicitis (AA), preoperative computed tomography (CT) findings suggesting development of intraabdominal abscess (IAA) had not been widely used. The aim of this study was to investigate the preoperative clinical and radiological factors that predict the development of a postoperative IAA in patients with AA who were treated by laparoscopic appendectomy (LA). Methods: Two hundred and sixteen patients with pathologically proven AA underwent LA between January 2013 and March 2018 in our department. Medical records and preoperative CT images of these 216 patients were retrospectively reviewed and the predictive factors of postoperative IAA were investigated. In addition, patients were divided into complicated appendicitis (CA) and simple appendicitis (SA) and perioperative factors of two groups were compared. Results: One hundred and forty-seven patients were diagnosed with CA, while the other 69 patients were diagnosed with SA. Sixteen patients developed postoperative IAA in the CA group, while no patients in the SA group did. The univariate analysis revealed that time from onset to surgery more than 3 days (p = 0.011), the preoperative CT finding of periappendiceal fluid (p = 0.003), abscess (p < 0.001), and free air (p < 0.001), operation time more than 120 min (p = 0.023) and placement of a drainage tube (p < 0.001) were significantly associated with the development of IAA. Multivariate analysis revealed that the preoperative CT finding of free air was independently associated with the development of IAA (p = 0.007, odds ratio = 5.427, 95% CI: 1.586–18.57). Conclusions: IAA developed predominantly in patients with CA. Preoperative CT findings of free air was found to be an independent predictor for the development of IAA. Surgeons should be meticulous in managing the postoperative course of patients with this finding.

We herein describe a patient on hemodialysis with advanced squamous cell lung cancer who was treated with chemotherapy that consisted of carboplatin(CBDCA)and paclitaxel(PTX). A 54-year-old man who was undergoing a routine hemodialysis for chronic renal failure presented with cold symptoms and was prescribed antibiotics.As no symptomatic improvement was achieved, he was referred to the Department of Internal Medicine in our hospital, where computed tomographic scan findings raised the suspicion of lung cancer.He was then referred to the Department of Surgery.A bronchoscopy detected a tumor, which obstructed the right upper lobe bronchus, and the patient was diagnosed with squamous cell carcinoma.Based on the mediastinal lymph node enlargement that extended into the contralateral hilar region, the stage was determined to be III B(c-T3N3M0), and we initiated chemotherapy.The regimen was CBDCA plus PTX.The carboplatin dose area under the curve(AUC)was 4(100 mg at a glomerular filtration rate of 0)for the first course, AUC 5 for the second course, and AUC 6 for the third to sixth courses, and the PTX dose was 200mg/m2.Only mild adverse events were noted, and the patient achieved a partial response after 6 treatment courses.Only a few reports have described chemotherapies administered to patients with lung cancer on hemodialysis, and as such, evidence of useful drugs is not yet available.This makes it difficult to select the most appropriate treatment for such patients.We report our experience with this patient, with a relevant literature review.

Laparoscopic lateral pelvic lymph node dissection (LLND) has been reported to be feasible; however, studies comparing the outcomes of laparoscopic LLND with that of open LLND following preoperative chemoradiotherapy (CRT) are limited. Between November 2005 and October 2017, 38 patients with locally advanced rectal cancer underwent total mesorectal excision and LLND following preoperative CRT at Kobe University Hospital. The data of the patients who underwent open LLND (OP group, n = 19) and laparoscopic LLND (LAP group, n = 19) were retrospectively collected and compared. The operative time was significantly longer in the LAP group compared with that in the OP group. However, the volume of blood loss was significantly higher, and transfusion was more frequently performed in the OP group than in the LAP group. The number of LLNs harvested in the LAP group was significantly higher than that in the OP group. The prevalence of perineal wound infection and bowel obstruction was significantly higher in the OP group than in the LAP group. However, no significant differences were observed between the groups in terms of 5-year overall survival, relapse-free survival, and local recurrence-free survival. Laparoscopic LLND is feasible and safe for patients with rectal cancer who were treated with preoperative CRT. Compared with open LLND, laparoscopic LLND might have several advantages such as higher yields of dissected LLNs and lower incidences of perineal wound infection and bowel obstruction.

Introduction Anatomical evaluation of the splenic flexure vein is essential for complete mesocolic excision with central vascular ligation when treating patients with splenic flexure cancer. Although there have been several studies relating to the arterial branches of the splenic flexure, very limited data are available regarding the variation in venous anatomy in this region. Methods Sixty-six patients with colorectal cancer who underwent preoperative 3-D CT between April 2016 and April 2017 were included in this retrospective study. The pattern of the venous drainage of the splenic flexure and its association with the inferior border of the pancreas were evaluated. Results The inferior mesenteric vein flowed into the splenic vein in 32 patients (48.5%), into the superior mesenteric vein in 27 patients (40.9%), and into the confluence of splenic vein and superior mesenteric vein in 7 patients (10.6%). The splenic flexure vein joined the inferior mesenteric vein in 62 patients (93.9%), the splenic vein in 2 patients (3.0%), and the middle colic vein in 2 patients (3.0%). The splenic flexure vein flowed into the inferior mesenteric vein below the level of the inferior border of the pancreas in 58 patients (90.6%) and above it in 4 patients (6.3%). Conclusion Preoperative evaluation of the venous pattern of the splenic flexure on 3-D CT is useful before complete mesocolic excision with central vascular ligation to avoid intraoperative bleeding during splenic flexure cancer surgery.

A 27-year-old woman was diagnosed with gastric cancer complicated peritoneal dissemination and direct invasion to pancreas via staging laparoscopy. After systemic chemotherapy using regimen of S-1/CDDP for 2courses, the tumor did not increase in size and peritoneal dissemination did not progress. The patient subsequently underwent distal gastrectomy as a curative surgery. The histological diagnosis was ypT4bN1M0, ypStage III B. The patient was treated with DOC/CDDP for 6 courses after surgery as adjuvant therapy. At present 6 years after surgery, the patient is alive without tumor recurrence.

Early laparoscopic cholecystectomy (ELC) is considered the standard treatment for acute cholecystitis for patients who can tolerate surgery. The ideal time for performing ELC is reported to be 72 h from onset. However, many patients undergo surgery on or after the fourth day from onset, even if they presented early after onset. A few reports have investigated the feasibility and disadvantages of this so-called "postponed laparoscopic cholecystectomy" (PLC).This study consisted of 215 patients who had undergone laparoscopic cholecystectomy for acute cholecystitis within 6 days of onset between July 2006 and December 2017. Patients were divided into an ELC group (patients who underwent LC within 3 days of symptom onset, n = 172) and a PLC group (patients who underwent LC 4-6 days from symptom onset and on or after 3 days from admission, n = 43). Comparisons were made between these groups.Perioperative outcomes between the PLC and ELC groups were not significantly different, except for the requirement of subtotal cholecystectomy (SC) (16.2% vs 5.2%, P = 0.013). In the PLC group, persistent fever after admission was significantly associated with the need for SC (P = 0.036).PLC for acute cholecystitis performed within 6 days of onset gave acceptable perioperative outcomes, except for an increased requirement for SC. Surgeons should keep in mind that PLC may increase the need for SC. A persistent fever after admission may be a risk factor for SC in the PLC group.

Debate continues regarding the clinical outcomes of early laparoscopic cholecystectomy (ELC) versus delayed laparoscopic cholecystectomy (DLC) for acute cholecystitis (AC). The aim of this retrospective study was to compare clinical outcomes of ELC and DLC.This study consisted of 465 patients who had undergone laparoscopic cholecystectomy for AC between January 2000 and February 2017. Patients were divided between an ELC group (patients who underwent laparoscopic cholecystectomy within 6 days of symptom onset, n = 288) and a DLC group (patients who underwent laparoscopic cholecystectomy at least 7 days from symptom onset, n = 177), and clinical outcomes were compared.Operation time (105 vs 124 min), length of postoperative hospital stay (4 vs 4 days), conversion rate (1.3% vs 10.7%), bile leak (0.3% vs 3.3%), residual calculus (2.4% vs 6.7%), and readmission (1.0% vs 6.7%) were significantly better in the ELC group. A history of upper abdominal surgery, grade II or grade III AC, preoperative percutaneous transhepatic gallbladder drainage, and time between symptom onset and surgery of more than 7 days were independent risk factors for conversion.ELC for AC yields more favorable clinical outcomes than DLC.

We carried out in vivo experiments of cultured flat pearl production using disc-like hydroxyapatite (HAp) bioceramics as a nucleus, with and without electric polarization treatment, and evaluated the effects of electric polarization and the quality of HAp materials on flat pearl formation. The thickness of the lamellar structures of the nacreous aragonite layers increased when polarized HAp pellets, instead of nonpolarized HAp pellets, as the nucleus, were used as the nuclei, while the thickness of the columnar structures of the prismatic calcite layers decreased. These phenomena were observed remarkably on the negative potential surface of the polarized HAp pellet. The electric polarization treatment promoted the formation rate of the nacreous lamella structure. It was speculated that electric polarization may control the physiological actions of mantle tissue and regulate the formation of the prismatic calcite and nacreous aragonite layers. The polarization treatment leads to an interference color with ...

This study demonstrates that electrical polarization inhibited low-temperature degradation (LTD) of yttria-stabilized zirconia (YSZ). Electrical polarizations, which were confirmed by the thermally stimulated depolarization current (TSDC) measurements, were induced by an applied dc voltage. The induced polarizations caused hydrophilic surfaces. The more hydrophilic the surfaces became, the more resistant they became to degradation. We propose a mechanism of LTD inhibition in which the electric repulsive force induced by the polarizations prevented the invasion of water into the inner part of the YSZ.

We studied theoretically and experimentally the effects of the surface electric field generated by polarization and polyacrylic acid (PAA) additives on the heterogeneous nucleation of calcite on the calcite single crystal substrates with (10.4), (10.0) and (00.1) orientations. A set of “in-situ” experiments with optical microscopy was performed to determine the waiting time of CaCO3 nucleation, defined as the time interval between the onset of the diffusion of CO2 and the appearance of the first visible precipitation. Calcite was nucleated on the oriented calcite substrates through diffusion of NH3 and CO2 gas from a solid ammonium carbonate into calcium chloride solutions. A theoretical analysis showed that the surface electric field of the polarized calcite substrate decrease the activation energy for nucleation and consequently promotes nucleation. Experimentally, the surface electric field and PAA addition were found to decrease both contact angles and waiting times, and as a result, promote the heterogeneous nucleation. Combined effect of PAA and surface electric field further reduced contact angles and waiting times regardless of orientation differences of the calcite substrates. The cooperation acts remarkably on N-surface of the respective calcite substrates. The results were explained by the Cassie׳s equation, a classical heterogeneous nucleation theory under a surface electric field, and matching of the charged sites on the PAA chain with the ion arrangement on the calcite substrate.

Laparoscopic surgery is a minimally invasive surgery, and the incidence of postoperative small bowel obstruction (SBO) is not high. However, SBO is a disease that detracts from the benefits of laparoscopic surgery due to the need for additional therapies or prolongation of hospital stay. Seprafilm is effective in reducing adhesions and preventing the occurrence of SBO. However, it is very difficult to place the Seprafilm during laparoscopic surgery compared to open surgery. Herein, we report a simple and easy method. The Seprafilm including the holder paper is divided into six pieces; each piece is wound around the end of the forceps and the reduction sleeve is slid over it. The forceps with the reduction sleeve is inserted through a 12-mm trocar and moved closer to the target place. Then, the reduction sleeve is slid down the forceps to expose the Seprafilm. This method does not require any special preparation or training. Based on our experience, this method can easily overcome the problems that the Seprafilm is vulnerable to tear and is difficult to spread out in the abdominal cavity.

This study investigated the surface characteristics and antibacterial ability capacity of surface-improved dental glass-ceramics by an electrical polarization process. Commercially available dental glass-ceramic materials were electrically polarized to induce surface charges in a direct current field by heating. The surface morphology, chemical composition, crystal structure, and surface free energy (SFE) were evaluated using scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, and water droplet methods, respectively. The antibacterial capacity was assessed by a bacterial adhesion test using Streptococcus mutans. Although the surface morphology, chemical composition, and crystal structure were not affected by electrical polarization, the polar component and total SFE were enhanced. After 24 h incubation at 37ºC, bacterial adhesion to the polarized samples was inhibited. The electrical polarization method may confer antibacterial properties on prosthetic devices, such as porcelain fused to metal crowns or all ceramic restorations, without any additional bactericidal agents.

Nonylphenol ethoxylate (NPE) is a non-ionic surfactant, that is degraded to short-chain NPE and 4-nonylphenol (NP) by bacteria in the environment. NP, one of the most common environmental endocrine disruptors, exhibits weak estrogen-like activity. In this study, we investigated whether oral administration of NP (at 0.5 and 5 mg/kg doses) affects spatial learning and memory, general activity, emotionality, and fear-motivated learning and memory in male and female Sprague-Dawley (SD) rats. SD rats of both sexes were evaluated using a battery of behavioral tests, including an appetite-motivated maze test (MAZE test) that was used to assess spatial learning and memory. In the MAZE test, the time required to reach the reward in male rats treated with 0.5 mg/kg NP group and female rats administered 5 mg/kg NP was significantly longer than that for control animals of the corresponding sex. In other behavioral tests, no significant differences were observed between the control group and either of the NP-treated groups of male rats. In female rats, inner and ambulation values for animals administered 0.5 mg/kg NP were significantly higher than those measured in control animals in open-field test, while the latency in the group treated with 5 mg/kg NP was significantly shorter compared to the control group in step-through passive avoidance test. This study indicates that oral administration of a low-dose of NP slightly impairs spatial learning and memory performance in male and female rats, and alters emotionality and fear-motivated learning and memory in female rats only, The Journal of Toxicological Sciences, 40(1), pp.43-53; 2015

Background The periodontal ligament (PDL), which maintains homeostasis in the periodontium, is a group of specialized connective tissue fibers attached to both the cementum and alveolar bone. Regeneration of periodontium with PDL cells has been investigated, and the chemical and molecular structures of scaffolds control the adhesion and differentiation of cells. Therefore, the development of adequate materials for PDL-derived cells is essential to regenerate the periodontium. Objective We evaluated the suitable passage time for PDL-derived cells and investigated the behaviors of PDL-derived cells grown on hydroxyapatite (HAp) scaffolds coated with type I and type III collagen. Methods PDL-derived cells were isolated with enzyme from the upper molars of male Wister rats. After characterization of HAp, type I collagen, and type III collagen, PDL-derived cells at passage 2 were seeded onto collagen-coated HAp. Cell adhesion, proliferative potential, and osteoconductivity were analyzed with immunostaining, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, Alizarin S staining, and real-time polymerase chain reaction. Results Type I and III collagens were successfully coated on HAp. Gene expression analysis revealed that passage 2 was suitable for maintaining differentiation potential. Proliferative potential and cell adhesion were significantly higher on type III collagen than on HAp alone or type I collagen. In contrast, the osteoconductivity of type III collagen was significantly lower than those of HAp and type I collagen. Conclusion PDL-derived cells on type I collagen differentiated into osteogenic cells and formed hard tissues. However, type III collagen enhanced the adhesion of PDL-derived cells and inhibited mineralization.

Recently, several new imaging technologies, such as three-dimensional (3D)/high-definition (HD) stereovision and high-resolution two-dimensional (2D)/4K monitors, have been introduced in laparoscopic surgery. However, it is still unclear whether these technologies actually improve surgical performance. Participants were 11 expert laparoscopic surgeons. We designed three laparoscopic suturing tasks (task 1: simple suturing, task 2: knotting thread in a small box, and task 3: suturing in a narrow space) in training boxes. Performances were recorded by an optical position tracker. All participants first performed each task five times consecutively using a conventional 2D/HD monitor. Then they were randomly divided into two groups: six participants performed the tasks using 3D/HD before using 2D/4K; the other five participants performed the tasks using a 2D/4K monitor before the 3D/HD monitor. After the trials, we evaluated the performance scores (operative time, path length of forceps, and technical errors) and compared performance scores across all monitors. Surgical performances of participants were ranked in decreasing order: 3D/HD, 2D/4K, and 2D/HD using the total scores for each task. In task 1 (simple suturing), some surgical performances using 3D/HD were significantly better than those using 2D/4K (P = 0.017, P = 0.033, P = 0.492 for operative time, path length, and technical errors, respectively). On the other hand, with operation in narrow spaces such as in tasks 2 and 3, performances using 2D/4K were not inferior to 3D/HD performances. The high-resolution images from the 2D/4K monitor may enhance depth perception in narrow spaces and may complement stereoscopic vision almost as well as using 3D/HD. Compared to a 2D/HD monitor, a 3D/HD monitor improved the laparoscopic surgical technique of expert surgeons more than a 2D/4K monitor. However, the advantage of 2D/4K high-resolution images may be comparable to a 3D/HD monitor especially in narrow spaces.

Obturator hernia is a rare clinical condition that causes intestinal obstruction. Recent reports have suggested that laparoscopic repair may be useful for incarcerated obturator hernia in select patients. The patient was a 64-year-old female who presented to our emergency department with a chief complaint of abdominal pain. Computed tomography (CT) imaging revealed an incarcerated obturator hernia on her right side, without apparent findings of irreversible ischaemic change or perforation. She had a previous history of cardiovascular surgery and was taking an anticoagulant medication. We performed a reduction of the incarcerated intestine. After heparin displacement, laparoscopic repair was electively performed. During laparoscopy, an occult obturator hernia was found on the left side. We repaired the bilateral obturator hernia using a mesh prosthesis. Elective laparoscopic repair after reduction might be a useful procedure for incarcerated obturator hernias in those patients without findings of irreversible ischaemic change or perforation.

Background There are few reports of Low-intensity pulsed ultrasound (LIPUS) treatment for fresh forearm fractures in children. Objectives LIPUS stimulation was applied after surgery of forearm fractures in children and the efficacy and safety of combination therapy of LIPUS treatment were evaluated. Patients and methods Children with both radius and ulna fracture, twenty-five diaphysis (mid-R&U) and nineteen metaphysis (dist-R&U) fractures, were treated with intramedullary nailing followed by cast and splint mobilization. Thirteen patients in the mid-R&U fracture group and eight patients in the dist-R&U fracture group were combined with LIPUS stimulation postoperatively. Results Periosteal callus appeared significantly earlier after surgery in the LIPUS-treated groups than in the groups without LIPUS treatment. The duration of external fixation was significantly shorter in the dist-R&U fracture group treated with LIPUS stimulation compared with that in the mid-R&U fracture group without LIPUS treatment. Furthermore, the time span needed for bone union in the groups with LIPUS stimulation was significantly shorter than in the groups without LIPUS stimulation. Conclusions It is suggested that LIPUS stimulation can lead to a reduction of treatment periods of unstable forearm fractures safely after operation even in children.

BACKGROUND Malignant tumors inhibit antitumor immune responses, which are driven by T-regulatory cells or myeloid-derived suppressor cells (MDSCs). Since MDSCs are involved in invasion, migration, and metastasis of tumor cells, we hypothesized that MDSCs are also involved in tumor recurrence after surgical resection. MATERIALS AND METHODS C57BL/6 mice were subcutaneously inoculated with B16F10 melanoma cells in the right flank. In some experiments, established tumors were surgically resected. Peripheral blood was drawn over time, and immune cells and cytokines were evaluated using flow cytometry. RESULTS MDSCs and relevant pro-inflammatory cytokines increased in the peripheral blood of tumor-bearing mice. Moreover, the frequency of MDSCs rapidly increased in mice with tumor recurrence. CONCLUSION The frequency of MDSCs in the peripheral blood of tumor-bearing mice reflects the status of tumor progression as well as tumor recurrence. Continuous monitoring of MDSCs in the peripheral blood might be a useful indicator of tumor recurrence.

Strangulation of the gallbladder associated with the omentum is extremely rare and, to our knowledge, only two cases have been previously reported. The patient was a 91-year-old female who presented to our emergency room with a chief complaint of upper abdominal pain. Computed tomography imaging revealed a gourd-shaped gallbladder with biphasic appearance divided clearly at the body. In the fundus side, the wall of the gallbladder was oedematous and thickened, while the neck side was intact. On the second day after onset, a laparoscopic cholecystectomy was performed. A tip of the omentum encircling the gallbladder was adhered to the abdominal wall and was strangling the gallbladder. By cutting the omentum at the attachment site, the strangulation was released. Laparoscopic cholecystectomy was performed, and the patient was discharged with an uneventful course. We experienced an extremely rare case of strangulated gallbladder caused by a tip of the omentum attached to the abdominal wall.

To treat colon cancer via complete mesocolic excision (CME) with central vascular ligation (CVL), dissection along the embryologic fusion planes is required. However, this surgery is difficult, especially for right-sided colon cancer, because the anatomy and embryology of the transverse mesocolon are not familiar to gastrointestinal surgeons. In this video article, the anatomic details of the transverse mesocolon based on embryology are illustrated with a focus on the venous anatomy. Dissection of the transverse mesocolon along the embryologic planes using a cranial approach during laparoscopic right hemicolectomy also is presented. During the development of the primitive gastrointestinal tract, the transverse mesocolon locates between the terminal portion of the midgut and the beginning of the hindgut. After 270° counterclockwise rotation of the primary intestinal loop, the transverse mesocolon fuses with the frontal surface of the duodenum and pancreas. Simultaneously, the greater omentum hangs down from the greater curvature of the stomach in front of the transverse colon and fuses with the transverse mesocolon. Moreover, the drainage vein of the right colon sometimes joins the right gastroepiploic vein, and the gastrocolic trunk is formed. Anatomic complexity of the transverse mesocolon is caused by rotation and fusion of the gastrointestinal tract during embryologic development. Knowledge concerning these embryologic peculiarities of the transverse mesocolon should be useful in the performance of laparoscopic CME with CVL for right-sided colon cancer.

BACKGROUND/AIM The aim of this study was to evaluate the safety and effectiveness of laparoscopic surgery in elderly patients with colorectal cancer. PATIENTS AND METHODS In total, 223 patients aged

Background Glioblastoma multiforme (GBM) is a malignant brain tumor with an extremely poor prognosis. GBM tissues frequently express mesenchymal-epithelial transition factor (MET), which induces cell division, growth and migration. In addition, angiogenesis is a significant feature of GBM, attributable to the overexpression of vascular endothelial growth factor (VEGF). Although the VEGF inhibitor bevacizumab was recently highlighted as the second-line drug for GBM treatment, GBMs often recur even with bevacizumab therapy. Based on these findings, we hypothesized that inhibition of both MET and VEGF would exhibit a synergistic effect on MET-overexpressing GBM. Materials and methods As we observed MET expression at high levels in some patients with GBM, we designed GL261 murine glioma-based experiments. GL261 cells were transfected with siRNAs specific for MET and VEGF in vitro, and the cell growth ratios were evaluated. Simultaneously, transfected GL261 cells were transplanted into the brain of C57BL/6 mice, and their survival was monitored. Results GBM tissues frequently overexpressed MET protein at high levels compared with lower-grade gliomas. These GBMs at first responded to bevacizumab, but often eventually recurred. When GL261 cells were co-transfected with both MET-specific siRNA and VEGF-specific siRNA, the in vitro tumor cell growth significantly decelerated compared to single siRNA transfection. Consistently, when mice were transplanted with co-transfected GL261 cells, their survival was significantly prolonged compared to those given cells transfected with single siRNA. Conclusion The current data indicate that the inhibition of both MET and VEGF exhibits efficient therapeutic effects of GBM-bearing hosts.

Bacterial adhesion to dental materials is a major cause of caries and periodontitis, necessitating the development of compounds such as yttria-stabilized zirconia (YSZ) and silver nanoparticles (AgNPs), which are widely employed in medicine due to their high antimicrobial activity and low cytotoxicity. The main goal of this study is the synthesis of the broad antimicrobial activity of AgNP-coated YSZ with facile methods. The bactericidal AgNPs were immobilized on the surface of YSZ and tested for bactericidal activity against Staphylococcus aureus, Streptococcus mutans, Escherichia coli, and Aggregatibacter actinomycetemcomitans based on ISO 22196:2007. The loading of AgNPs was optimized by culturing mouse fibroblast cells on AgNP-coated YSZ with cell viability test based on ISO 10993-5. In addition, the silver release profile of AgNP-coated YSZ in artificial saliva was determined using an accelerated aging test. Antibacterial activity, and cell viability test revealed optimum performance with no cytotoxicity at a level of 32 μg/cm2. Accelerated aging test showed that the AgNP-coated surface was extremely stable, exhibiting a total silver leaching level of only 1% and confirming the effectiveness of this coating method for retaining AgNPs while exerting an antibacterial effect against oral pathogens. This finding also implies that the bactericidal action of AgNP-coated YSZ is not mediated by the released Ag ions, but rather corresponds to contact killing. Abbreviations: Yttria-stabilized zirconia, YSZ; silver nanoparticles, AgNPs; field emission scanning electron microscopy, FE-SEM; X-ray photoelectron spectroscopy, XPS; grazing incidence X-ray diffraction, GIXRD; ultraviolet-visible, UV-vis; inductively coupled plasma atomic emission spectrometry, ICP-AES.

Using a wet method, we have synthesized octacalcium phosphate carbonate, in which HPO42- in octacalcium phosphate is replaced with CO32-. The physical, crystal, and chemical properties of this new material were compared to octacalcium phosphate, Ca-deficient hydroxyapatite, and Ca-deficient carbonate apatite using X-ray diffraction, Fourier-transform infrared spectroscopy, inductively coupled plasma spectroscopy, and scanning electron microscopy. Surface roughness and morphology were also characterized, along with the ability to support proliferation and differentiation of MG63 cells, as measured by MTT and alkaline phosphatase assay. We found that octacalcium phosphate carbonate enhanced osteoblast proliferation more strongly than all other materials tested. Similarly, Ca-deficient carbonate apatite, a hydrolysate of octacalcium phosphate carbonate, stimulated osteoblast differentiation to a better extent than Ca-deficient hydroxyapatite, a carbonate-free hydrolysate of octacalcium phosphate. These results indicate that octacalcium phosphate carbonate has good biocompatibility and osteoconduction, and incorporation of carbonate into octacalcium phosphate and apatite enhances bone regeneration.

Recent technical improvements allow safe laparoscopic lymph node dissection (LND) in gastric cancer.1After LND around the CHA and right side of the CA from the patient's right side, the surgeon then moves to the patient's left side. The anterior pancreatic fascia is cut at the middle point of the SA to discern the dorsal layer of the LN along the SA, such as the splenic vein. LND is performed by preserving the posterior pancreatic fascia around the SA in a left-to-right direction. Finally, the LNs around the left side of the CA are deeply dissected.We performed this procedure on ten patients between April 2016 and January 2017; no operative complications were reported in grade II or higher cancer patients.3 After exposing the dorsal landmark, LNs around the proximal SA and left side of the CA were removed in all patients.This procedure enables early identification of the dorsal layer and deep LND around the left side of the CA, keeping this layer. The left lateral approach is useful for radical LND along the proximal SA.

No consensus has been reached with regard to the optimal treatment strategy and the prognosis of patients with advanced rectal cancer and inguinal lymph node metastasis. We, therefore, retrospectively analyzed the outcomes of 41 patients with locally advanced rectal cancer who underwent surgery after neoadjuvant chemoradiotherapy(NACRT). Six patients, with clinical inguinal lymph node metastasis determined by pretreatment imaging, underwent inguinal lymph node dissections after NACRT. Five patients survived without a relapse. Only 1 patient, who had been diagnosed with pathological inguinal lymph node metastasis, had a relapse in the right iliac lymph node 6 years after surgery. Surgical treatment after NACRT for rectal adenocarcinoma with inguinal lymph node metastasis contributes to an improvement in outcomes. NACRT plus inguinal lymph node dissection is an effective strategy for patients with inguinal lymph node metastasis from rectal adenocarcinoma.

Micro-/nanostructured implant surfaces mimicking natural bone architecture are expected to have positive effects on osteoblast proliferation. In this study, to clarify the optimal microstructure scale on micro-/nano-titanium surfaces, highly controlled microstructure surfaces were fabricated with a titania nanotube oxide layer by sandblast treatment and electrochemical anodization. Average surface roughness (R

@font-face { font-family: "ＭＳ 明朝"; }@font-face { font-family: "Cambria Math"; }@font-face { font-family: "@ＭＳ 明朝"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0mm 0mm 0.0001pt; font-size: 10pt; font-family: "Times New Roman"; }.MsoChpDefault { font-size: 10pt; }div.WordSection1 { page: WordSection1; } Bioresorbable materials may be advantageous for use in bone regeneration applications because they do not leave residues of foreign material, improving the long-term success of implant restoration. The purpose of this study was to investigate the osteoclastogenesis and bioresorption of synthesized calcium phosphate ceramic materials for orthopaedic and dental biomaterial applications. Differentiation into mature human osteoclasts on carbonated hydroxyapatite (CA) was significantly enhanced compared to hydroxyapatite (HA). Osteoclasts derived from human peripheral mononuclear blood cells adhered and differentiated into giant multinuclear TRAP- positive cells on every type of synthesized sample based on the histological analysis. Morphological observations using fluorescence and quantitative analysis revealed that the actin rings of osteoclasts on CA were thick and small in diameter, similar to the rings found on bone slices. Scanning electron microscopic images and quantitative analysis indicated that the resorption pits on CA were significantly deeper than those on HA due to the enhanced tight sealing ability between osteoclasts and their substrate.

Thermally stimulated depolarization current (TSDC) measurements were performed on 3 mol% and 8 mol% yttria stabilized zirconia ceramics (3YSZ and 8YSZ), in order to observe defect associations. Several TSDC peaks were observed, and the characteristics suggested that the peaks were attributed to space charge polarization due to long range migration of oxygen vacancies and electric dipole polarization due to trimeric defect association of Y at Zr site (Y Zr ') and oxygen vacancy (Vo). The activation energies for the dipole polarizations were different between 3YSZ and 8YSZ. The difference was caused by the difference of the structure of defect association. In addition, in 3YSZ, peaks with high activation energy of 1.24 eV were observed. The high activation energy suggests the presence of oxygen migration across Y–Y edges, in other word, indicating that Y–Y pairs exist in 3YSZ.

We demonstrated the crystallization of calcium carbonate (CaCO3) on polarized calcite single crystal substrates with three different orientations characterized by the (10.0), (00.1), and (10.4) planes in the presence of polyaspartic acid (PAsp) as an organic additive. The precipitates had a multiple phase structure with thin-film-like and hemispherical forms and were a mixture of calcite, aragonite, and vaterite. The main component of the thin-film-like layers was calcite elongated along the c-axis, regardless of the differently oriented calcite substrates, while the main component of the hemispherical layers was aragonite. The individual crystals of each CaCO3 polymorph shaped the morphology of the mesocrystals. Calcite-aragonite complex films with two distinct structures are similar to those found in pearls and bivalve shells. The combined effect of a surface electric field by virtue of the polarized calcite substrates and PAsp promoted the formation of the thin-film-like layers and moreover, acted remarkably on the negatively charged surface of each oriented calcite substrate. The matching between the β-sheets of PAsp and the calcium-ion arrangement on top of the oriented calcite substrates explained the preferential calcite crystallization in the form of the thin-film-like layers and why calcite precipitates are in the following sequence: (00.1)>(10.4)>(10.0).

Glass–ceramics of the phosphorus-containing Na 5 RSi 4 O 12 -type (R = rare earth) Na + -superionic conductors were prepared by crystallization of glasses with the composition Na 3 + 3 x + y Y 1 − x − z R z P y Si 3 − y O 9 (NaYRPSi; R = Nd, Sm, Eu, Gd, Dy, Er, Yb) ( x = 0.4, y = 0.2, z = 0.1). The crystallization kinetics of the glasses was examined by DTA, and the effects of R elements on the separation of the phase and the microstructural effects on the conduction properties of glass–ceramics were discussed. The activation energy of crystal growth of the NaYRPSi glass decreases as the ionic radius of R is increased. The conductivity of the NaYRPSi glass–ceramics increases as the ionic radius of R is increased.

Titanium (Ti) is one of the most widely used for biomaterials, because of its excellent anti-corrosion and high mechanical properties. In addion to these properies, the bioactivity of Ti is required. Recently, coating of the titanium dioxide (TiO2) film on Ti plate surface is useful methods to obtain biocompatibility of Ti plate. If periodic nanostructures were formed on the film surface, direction of cell spreading might be controlled due to grooves direction. Then, femtosecond laser is one of the useful tools of periodic nanostructures formation. Peiriod of periodic nanostructures might be varied by changing the laser wavelength. In the experiments, the film was formed on Ti plate with an aerosol beam which was composed of submicron size TiO2 particles and helium gas. The film was irradiated with the femtosecond laser. Laser wavelengths of the laser was at 1044, 775 and 388 nm, respectively. Periodic nanostructures, lying perpendicular to the laser electric field polarization vector, were formed on the film by femtosecond laser irradiation at 1044, 775 and 388 nm, respectively. The period of the periodic nanostructures on the film produced by femtosecond laser irradiation at 1044, 775 and 388 nm was about 350, 230 and 130 nm, respectively. In the cell test, cell spreading along the grooves of the periodic nanostructures was observed although it was not done for the film without the periodic nanostructures. These results suggested that direction of cell spreading could be controlled by the periodic nanostructures formation